[PATCH v5 01/15] scsi: ufs-qcom: add number of lanes per direction

Yaniv Gardi
2016-02-28T13:32:33Z

Different platform may have different number of lanes
for the UFS link.
Add parameter to device tree specifying how many lanes
should be configured for the UFS link.

Signed-off-by: Gilad Broner <gbroner@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>

---
.../devicetree/bindings/ufs/ufshcd-pltfrm.txt | 3 ++
drivers/scsi/ufs/ufs-qcom.c | 39 ++++++++++++----------
drivers/scsi/ufs/ufshcd-pltfrm.c | 19 +++++++++++
drivers/scsi/ufs/ufshcd.c | 1 +
drivers/scsi/ufs/ufshcd.h | 2 ++
5 files changed, 47 insertions(+), 17 deletions(-)

diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
index 03c0e98..66f6adf 100644
--- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
+++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
@@ -38,6 +38,9 @@ Optional properties:
defined or a value in the array is "0" then it is assumed
that the frequency is set by the parent clock or a
fixed rate clock source.
+-lanes-per-direction : number of lanes available per direction - either 1 or 2.
+ Note that it is assume same number of lanes is used both
+ directions at once. If not specified, default is 2 lanes per direction.

Note: If above properties are not defined it can be assumed that the supply
regulators or clocks are always on.
diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 4f38d00..ed57729 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2013-2015, Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2016, Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
@@ -132,21 +132,24 @@ static int ufs_qcom_enable_lane_clks(struct ufs_qcom_host *host)
if (err)
goto disable_rx_l0;

- err = ufs_qcom_host_clk_enable(dev, "rx_lane1_sync_clk",
- host->rx_l1_sync_clk);
- if (err)
- goto disable_tx_l0;
+ if (host->hba->lanes_per_direction > 1) {
+ err = ufs_qcom_host_clk_enable(dev, "rx_lane1_sync_clk",
+ host->rx_l1_sync_clk);
+ if (err)
+ goto disable_tx_l0;

- err = ufs_qcom_host_clk_enable(dev, "tx_lane1_sync_clk",
- host->tx_l1_sync_clk);
- if (err)
- goto disable_rx_l1;
+ err = ufs_qcom_host_clk_enable(dev, "tx_lane1_sync_clk",
+ host->tx_l1_sync_clk);
+ if (err)
+ goto disable_rx_l1;
+ }

host->is_lane_clks_enabled = true;
goto out;

disable_rx_l1:
- clk_disable_unprepare(host->rx_l1_sync_clk);
+ if (host->hba->lanes_per_direction > 1)
+ clk_disable_unprepare(host->rx_l1_sync_clk);
disable_tx_l0:
clk_disable_unprepare(host->tx_l0_sync_clk);
disable_rx_l0:
@@ -170,14 +173,16 @@ static int ufs_qcom_init_lane_clks(struct ufs_qcom_host *host)
if (err)
goto out;

- err = ufs_qcom_host_clk_get(dev, "rx_lane1_sync_clk",
- &host->rx_l1_sync_clk);
- if (err)
- goto out;
-
- err = ufs_qcom_host_clk_get(dev, "tx_lane1_sync_clk",
- &host->tx_l1_sync_clk);
+ /* In case of single lane per direction, don't read lane1 clocks */
+ if (host->hba->lanes_per_direction > 1) {
+ err = ufs_qcom_host_clk_get(dev, "rx_lane1_sync_clk",
+ &host->rx_l1_sync_clk);
+ if (err)
+ goto out;

+ err = ufs_qcom_host_clk_get(dev, "tx_lane1_sync_clk",
+ &host->tx_l1_sync_clk);
+ }
out:
return err;
}
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index d2a7b12..718f12e 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -40,6 +40,8 @@
#include "ufshcd.h"
#include "ufshcd-pltfrm.h"

+#define UFSHCD_DEFAULT_LANES_PER_DIRECTION 2
+
static int ufshcd_parse_clock_info(struct ufs_hba *hba)
{
int ret = 0;
@@ -277,6 +279,21 @@ void ufshcd_pltfrm_shutdown(struct platform_device *pdev)
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_shutdown);

+static void ufshcd_init_lanes_per_dir(struct ufs_hba *hba)
+{
+ struct device *dev = hba->dev;
+ int ret;
+
+ ret = of_property_read_u32(dev->of_node, "lanes-per-direction",
+ &hba->lanes_per_direction);
+ if (ret) {
+ dev_dbg(hba->dev,
+ "%s: failed to read lanes-per-direction, ret=%d\n",
+ __func__, ret);
+ hba->lanes_per_direction = UFSHCD_DEFAULT_LANES_PER_DIRECTION;
+ }
+}
+
/**
* ufshcd_pltfrm_init - probe routine of the driver
* @pdev: pointer to Platform device handle
@@ -331,6 +348,8 @@ int ufshcd_pltfrm_init(struct platform_device *pdev,
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);

+ ufshcd_init_lanes_per_dir(hba);
+
err = ufshcd_init(hba, mmio_base, irq);
if (err) {
dev_err(dev, "Initialization failed\n");
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 9c1b94b..a8e42df 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -40,6 +40,7 @@
#include <linux/async.h>
#include <linux/devfreq.h>

+#include <linux/of.h>
#include "ufshcd.h"
#include "unipro.h"

diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index e3931d0..9ae7f85 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -509,6 +509,8 @@ struct ufs_hba {

bool wlun_dev_clr_ua;

+ /* Number of lanes available (1 or 2) for Rx/Tx */
+ u32 lanes_per_direction;
struct ufs_pa_layer_attr pwr_info;
struct ufs_pwr_mode_info max_pwr_info;

--
1.8.5.2

--
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